Merge remote-tracking branch 'upstream/master' into eagletree

1 files changed, 26 insertions, 0 deletions

diff --git a/apps/position_estimator_mc/positionKalmanFilter1D_dT.m b/apps/position_estimator_mc/positionKalmanFilter1D_dT.m
new file mode 100755
index 000000000..f94cce1fb
--- /dev/null
+++ b/apps/position_estimator_mc/positionKalmanFilter1D_dT.m
@@ -0,0 +1,26 @@
+function  [x_aposteriori,P_aposteriori]=positionKalmanFilter1D_dT(dT,x_aposteriori_k,P_aposteriori_k,u,z,gps_update,Q,R,thresh,decay)
+    %dynamics
+    A = [1 dT -0.5*dT*dT;
+         0 1 -dT;
+         0 0 1];
+    B = [0.5*dT*dT; dT; 0];
+    C = [1 0 0];
+    %prediction
+    x_apriori=A*x_aposteriori_k+B*u;
+    P_apriori=A*P_aposteriori_k*A'+Q;
+    if abs(u)<thresh
+        x_apriori(2)=decay*x_apriori(2);
+    end
+    %update
+    if gps_update==1
+        y=z-C*x_apriori;
+        S=C*P_apriori*C'+R;
+        K=(P_apriori*C')/S;
+        x_aposteriori=x_apriori+K*y;
+        P_aposteriori=(eye(size(P_apriori))-K*C)*P_apriori;
+    else
+        x_aposteriori=x_apriori;
+        P_aposteriori=P_apriori;
+    end
+end
+